Nuclear Oncology

Posts Tagged ‘Brain Tumors’

A small initial test in children with medulloblastoma (most common type of childhood malignant brain tumor) showed that an experimental drug developed by Swiss drugmaker Roche Holding AG, may have promising results.

Baptized under the name ‘GDC-0449′, this drug is part of a new class of drugs that block the so-called ‘Hedgehog Signaling Pathway, which involves several proteins that play a role in cell growth.

Presented at a meeting of the American Society of Clinical Oncology, the results of the test phase showed that the drug was well tolerated by 12 of 13 children with medulloblastomas constant or resistant to drugs, with one patient who remained with the drug for more than a year without achieving progress against the disease.

Amar Gajjar Dr., director of neuro-oncology at Children’s Research Hospital St. Jude in Memphis, Tennessee, and lead investigator of the study, stressed that: “Less than 5 percent of these children survive if primary treatment fails.”

Gajjar found that the ‘hedgehog pathway’ was responsible for about 20 percent of medulloblastomas and future trials will involve patients whose tumors have activated hedgehog ducts.

In addition, earlier studies have suggested that GDC-0449 could also be effective against basal cell carcinoma in adults and there is currently a two-phase test is performed in adults with medulloblastoma recurrent.

Protons are atoms that have a positive charge. Like the X-rays are used to treat benign and malignant tumors, a beam of protons can be used to irradiate tumors in the same way. There are no differences between the biological effects of protons compared with photons (X rays). Physically, the protons release most of their energy when they hit the tumor and, unlike photons, do not apply a dose outside the boundaries of the tumor. Therefore, the radiation dose is best suited to the tumor and less damage to healthy tissue. As a result, the treating physician (an oncologist) can potentially give a higher dose to the tumor while minimizing unwanted side effects. This feature is particularly important in the treatment of children, reducing the radiation to tissue growth and development.

Proton therapy is being used to treat tumors in the following areas of the body with promising early results:

* Lung
* Prostate
* Brain
* Vertebral body tumors  or column
* Sarcomas of the skull base
* Pediatric Brain Tumors
* Head and neck (see page head and neck cancer
* Melanomas of the eye
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